import java.util.Scanner;

public class Main1155 {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int m = sc.nextInt();
        int[] num = new int[m];
        for (int i = 0; i < m; i++) {
            num[i] = sc.nextInt();
        }
        double sum=0.0;
        int b;

        for (int i=0;i< num.length;i++){
            sum=sum+num[i];

        } System.out.println(String.format("AVE=" + "%.1f", sum / m));
        double max = sum/m;
        for (int i=0;i< num.length;i++) {
            if (num[i] > max) {
                System.out.print(i+1+":"+num[i]+" ");
            }
        }
    }
}